igneous structural forms

folding and landforms

faulting and landforms


Structural forms: sedimentary rocks

Definition: landforms with a primary form controlled by differential weathering and erosion of different rock types and structures in sequences of sedimentary rock

The sedimentary rocks of East Lothian often form low ground in which the structure of the rocks is largely hidden from view. This subdued topographic expression is partly a result of glacial smoothing, itself a combination of rounding of exposed edges and smothering by glacial deposits. It is a also a reflection of the generally low dip of the Carboniferous succession and the weakness of many of its members relative to the igneous plus, vents, sills and lava flows.

The role of structure is most evident in the cliffs of the coast. Here the highest cliffs tend to be associated with thick beds of competent sandstone, with bays and low shores developed in thinly-bedded or softer layers. On shore platforms the gently-dipping sedimentary rocks often form mini cuestas, with thick beds of limestone or sandstone acting as cap rocks.